1. In a small saucepan, combine sugar and 1 cup of water, heating over medium while stirring until sugar fully dissolves to create a simple syrup.

2. Remove syrup from heat and allow it to cool completely.

3. In a large pitcher, combine fresh lemon juice, lime juice, pineapple juice, and cooled simple syrup.

4. Add the remaining 5 cups of cold water and stir well to combine.

5. Taste and adjust sweetness by adding more water or sugar if desired.

6. Add green food coloring one drop at a time, stirring until the desired vibrant green color is achieved.

7. Refrigerate for at least 1 hour until thoroughly chilled, then serve over ice and garnish with citrus slices. Add alcohol per glass or stir into the pitcher if making the adult version.